Christopher Stokes knows exactly how many paces it is from his office to the nearest police station.

The reason why such detailed intelligence is necessary becomes clear with one glance at the latest physical threat emailed to Stokes' Blackberry from yet another anonymous criminal.

Stokes, chairman and CEO of NetResult, and his 15-strong team are paid by some of the biggest clients in world sport to scour the internet 24 hours a day, ensuring any illegal live videos and highlights clips are quickly blocked and removed.

Some of those responsible for providing this illegal content, particularly live streaming of football matches on broadband, are making extremely profitable criminal careers out of doing so. But internet and mobile companies pay millions of pounds for the exclusive rights to such content and are unwilling to see their deals rendered worthless by the likes of YouTube and others.

Stokes is essentially chief constable of an internet police force, one with a remarkably high success rate when it comes to "collars''. "We probably nail 90 per cent of the unlicensed content that's out there, whether it be last night's goals that have been downloaded by kids on to user-generated sites such as YouTube, or some Chinese-based illegal live streaming of an English Premier League match.''

That success rate is what has ensured NetResult a client list that includes UEFA, Formula 1, and in America, the National Basketball Association. Last week the National Football League called from the States to talk to Stokes about using his services.

Success comes at a price, however. Having been chased and successfully closed down by Stokes' team, one internet pirate who had been selling subscriptions to his illegal live sports streaming site contacted Stokes to ask him which leg he'd rather lose. "We're used to receiving physical threats regularly. There's a lot of money to be made illegally,'' says Stokes with a smile. Though fairly imposing at 6ft 1in, Stokes is softly spoken with a gentle demeanour. His claim that he is a sports fan at heart is backed up by the 20 years this qualified chartered accountant worked for the International Tennis Federation.

But as well as being a lover of sports, Stokes says he is driven by the notion of providing a "good service to his clients''. Stokes believes he has employed the best technical experts to help him protect what rights owners have paid for. "Six of our team are Chinese nationals. Not only because internet sports piracy is huge in China, but because they are outstanding at what they do - they have a great knowledge and quickness when finding and breaking down infringements of rights.''

NetResult also boasts uniquely sophisticated automated search software. "We know pretty much everything that is happening illegally and when and where. We track all the major criminal activity but also hang about in sports chat rooms. People love to blab when they are illegally watching a televised match for free on the internet. They know it's illegal but only in the same way as Napster was so they don't necessary feel like they are breaking the law.''

According to Stokes, internet piracy is itself becoming more sophisticated with ever more ways for those responsible to camouflage themselves. "In some ways,'' he says, "it's really hard to sustain a consistent business model for more than six months at a time because we have to keep changing what we do and how we do it. Criminals will use software to create more barriers to hide behind so we have to be clever and solve new problems at every turn. Our technical knowledge has so far been good enough, -they haven't thrown us off just yet.''

Luckily for Stokes, a changing business model and the problems that would cause to investors isn't a problem. He and his chief technical officer Julian Searle are majority shareholders with enough profits coming in to avoid having to think about cashflow. He describes the company as too small to float but says there are plans for the future. "We don't just deal in sports but also police the abuse of company brands, logos and trademarks across the web. Companies here have no idea how they are represented, or mis-represented on blogs in say, China or Russia. We can monitor all that and help their brands become consistent around the world.''

NetResult is not yet a widely known name, but football fans used to seeing the weekend's top Premier League goals on YouTube will be well aware of it. Any fan who went looking for Steven Gerrard's wonder goal on YouTube following Liverpool's match against Aston Villa last weekend, will have been disappointed. The blocking of that goal, like many others with the words "This video is no longer available due to a copyright claim by NetResult'' provoked a fresh barrage of "e-rage'' to Stokes' email inbox. One reads: "I'm gonna **** you up you ****. I wanted to see Gerrard's sickest goal ever and you've blocked it you ****!''.

But the moral arguments are quite straightforward to Stokes. "I'm quite sensitive to the accusation that we are crushing the spirit of the internet. I could understand the abuse we get if the content wasn't freely available on the internet elsewhere.''

By now UK football fans are well aware that Setanta has challenged Sky's previous monopoly on televised Premier League games for the first time this season. But the fans who know Virgin Media has secured a three-year pounds 20m deal for the Premier League's exclusive UK mobile and internet rights will be few and far between. The Premier League, which is currently leading a class action against YouTube in New York, is keen to see effective policing and works exclusively with NetResult to achieve that. It sold its global internet and mobile rights to a number of partners and distributors for a total of pounds 200m. That figure is just less than a third of the pounds 650m received for its global TV rights, but growing fast with every passing contract.

With such a high value placed on NetResult's work it seems odd that Stokes and his team work from modest serviced offices. NetResult's headquarters in west London is bare and sparse-looking. Each staff member has an Ikea-regulation desk set out in school classroom formation. "It's a bit grubby but we don't want to waste management time on paying electricity or cleaning bills. We're profitable because we're cautious with money,'' he says, the chartered accountant coming out. It contrasts wildly with the plush, glass offices adorned with palm trees that house YouTube in Victoria. Careful not to mention YouTube by name because of the current court case, Stokes hints at a poor relationship with Google's most famous acquisition. "We're in discussion with lots of the user-generated sites about becoming licensed and seeking ways of acting within the law. Others are obviously confident in their legal position and are less inclined to talk.''

According to some, NetResult's software is better at dealing with crimes involving live video streaming than it is at outlawing clips and highlights packages of the sort seen on YouTube. Stokes says: "If somebody is screening live football illegally it is only going to last for 90 minutes, so when we spot it there isn't time to contact the rights owner. We send an email warning the perpetrator to shut down the service. Most just delete it, but we have very good relationships with the Internet Service Providers such as BT and AOL who can't afford to be seen to engage in illegal activity. The moment we alert them to what is going on they disconnect whoever is responsible.''

Stokes is secretive about the technology used, but says it enables NetResult to see any internet site in the world as if they were logging on from the local region the website serves. This is not something everyone can do; for example, a Premier League football fan in the US cannot watch Manchester United's match highlights on Virgin Media's website because Fox owns the Premier League's rights in America.

A frustrated insider from one of the global rights owners says: "NetResult is useless as an organisation. In terms of policing live streaming there is nobody else on their level, but when it comes to clips and goals uploaded on to sites like YouTube, it's virtually unpoliceable. We have to feed them information every time we spot an infringement of rights in one of our territories, hence we end up sitting searching the internet as much as they do. I'm not sure how much they are paid by the Premier League but we should get some of that fee.''

The source is correct in saying that goals clips are so difficult to regulate. YouTube is adamant that it isn't breaking the law. It says it will remove or block specific films that rights owners complain about but has no control over what is uploaded by users. This it argues, is within the requirements of the Digital Millennium Copyright Act. The moment it is alerted by NetResult to the fact illegal football footage has been posted, it will remove it, but not before. Therefore, as soon as one clip is taken down, somebody else can put their version of it back up on the site. Stokes describes the illegal use of clips on user-generated sites as a "Wild West'' but says NetResult is getting quicker at taking clips down as they appear.

"The value of sport is in live content,'' says Stokes. "Nobody watches a whole match three hours after it has happened if they already know the score. That's what our focus on criminal live streaming is all about. When it comes to clips we have to be careful to identify the clip in question - there's no blanket legislation we can rely on to make our job less labour intensive. We speak to YouTube several times every day.''